Electron gun structural support



1965 B. G. DOUGLASS ETAL 3,

ELECTRON GUN STRUCTURAL SUPPORT Filed Oct. 17, 1961 Fig. 3.

WITNESSES: INVENTORS Q Billy G. Douglass and @W Vincent J. Muccigrosso.

United States Patent 3,213,310 ELECTRON GUN STRUCTURAL SUPPQRT Billy G. Douglass, Horseheads, and Vincent J. Muccigrosso, Elmira, N.Y., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Oct. 17, 1961, Ser. No. 145,547 5 Claims. (Cl. 313- 82) This invention relates to the mounting of electrode structures within an envelope and more particularly to the mounting of an electron gun structure within an envelope of an electron discharge device.

In the conventional type electron gun now used in cathode ray tubes, the electron gun structure is of unitary construction. The gun normally consists of a plurality of electrodes assembled and mounted together to form a structure which may be inserted as a unit into the envelope or neck of the cathode ray tube. The gun consists of a plurality of spaced tubular electrodes with their axes lying on the axis of the neck portion of the cathode ray tube. A plurality of insulating rods are positioned along the outer periphery of the electrode assembly parallel to the axes of the electrodes. Pins or studs are secured to the outer periphery of the electrodes and are attached to the insulating rods. The studs are normally secured to the insulating rod by heating the insulating rod to a molten state and thereafter allowing the mate-rial to cool and thereby imbed the studs in the insulating rods. This provides a unitary structure of substantial strength and the electrodes are aligned and properly spaced during the process of sealing the stud members to the insulating rods.

The electron gun assembly as just described is then mounted to a glass button stem member. The glass stem member is sealed to the neck of the cathode ray tube to provide a vacuum tight seal. The button stem consists also of a plurality of electrically conductive lead-in members providing means of supplying the necessary potentials to the electrodes of the gun within the envelope. The lead-in members are welded to the electrodes and in addition mechanically support the electron gun on the stem member and accordingly within the neck of the cathode ray tube. The stem member is also provided with an exhaust tubulation used in processing the tube and, of course, is sealed off during processing. The front end of the electron gun, that is the portion projecting farthest into the neck of the cathode ray tube, is usually provided with centering means which positions the electron gun in the neck. This centering means in most cases also provides an electrical contact between a coating provided on the interior surface of the cathode ray tube and the anode of the electron gun.

It is, of course, obvious that during the assembly of the electron gun to the button stem and the insertions of the electron gun into the neck of the cathode ray tube, that substantial strain will be placed on the lead-in member which supports the electron gun upon the button stem. The normal practice is to utilize two or three lead-in members secured to the electrode member adjacent the button stem. In the conventional cathode ray tube this electrode is the control grid and these lead-in members are normally spot welded to the outer periphery of the tubular portion of the control grid. Another design prob lem that exists after the gun is inserted into the cathode ray tube is to provide adequate support to withstand vibration and other shocks during the normal operation of the tube. In some military applications these vibrations may involve accelerations of to G. In the conventional type structure where the lead-in wires are simply welded to the lower gun element experience has indicated that the welds and even the lead-in member itself fail to ice provide the necessary strength for supporting the electron gun from the button stem.

It is therefore an object of the present invention to provide an improved method of supporting an electron gun within an electron discharge tube.

It is another object to provide an improved electron gun structure to provide better mounting within a cathode ray tube.

It is another object to provide an improved means of supporting the electron gun with respect to the button stem portion of the cathode ray tube.

It is another object to provide an improved support structure which reinforces the conventional electron gun support structure presently used in cathode ray tubes.

According to the present invention, an electron gun support structure is provided which includes a clamping ring secured to the electrode element of the gun adjacent to the button stem with reinforcement holding means secured to or integral with the ring and through which the support lead-in members are inserted and secured thereto to reinforce the lead-in members along their length to the button stem and in addition secure the lead-in support members to the electrode member.

Further objects and advantages of the invention will become apparent as the following description proceeds and features of novelty which characterize the invention will be pointed out in particularity in the claims annexed to and forming a part of this specification.

For a better understanding of the invention, reference may be had to the accompanying drawings in which:

FIGURE 1 is an elevation view of an electron gun assembly mounted in an envelope in accordance with the present invention;

FIG. 2 is a section view of the electron gun structure of FIG. 1 taken along the line IIII; and,

FIG. 3 is a view previous to final forming of the clamping support member utilized in FIGS. 1 and 2 prior to incorporation therein.

Referring now to FIGS. 1 and 2, there is shown an electron gun 10 mounted in the neck portion 12 of a cathode ray tube envelope. The electron gun 10 is mounted to a button stem portion 14. The button stem portion 14 is sealed to the neck portion 12 of the cathode ray tube during the tube processing.

In the specific embodiment shown, the electron gun 10 consists of a control grid 20, a screen grid 22, and an anode 24 which are aligned and secured together to form a unitary structure by means of the insulating rod 40. Studs 42 are provided on the tubular electrode 20, 22 and 24 of the gun 10 and are sealed to the insulating rods 40 as previously discussed. The end of the electron gun which is farthest from the stem member 14 is centered within the neck portion 12 by means of a bulb spacer structure 26. A cathode electrode 43 and a heater (not shown) are provided within the control electrode 20. An annular clamping member 50 is secured to the lower portion of the outer periphery of a control electrode 20. The clamping member 50 includes a body portion 51 and at least three longitudinal extensions 52 which extend from the body portion 51 to substantially the button stem 14. A channel or a groove 54 is provided within the body portion 51 and the extensions 52 so as to receive support leads 56 from the button stem 14 to the control grid 20. One of the support leads 56 provides means of applying potential to the control grid 20 while the other two lead-in members 56 are simply utilized for supporting the electron gun structure with respect to the button stem 14. By this arrangement, it can be seen that the electron gun 10' is supported from the button stem 14 at at least three points positioned approximately apart by means of the support lead-ins 56. The reinforce- 3 ment and clamping ring 50, as clearly illustrated in FIG. 3, includes the body portion 51 provided with longitudinal grooves or eyelets 54 which extend into the extension portions 54. It will be seen that the support member ofiers excellent centering of that end of the gun adjacent to the stern member.

The normal assembly procedure is to spot weld the body portion 51 of the clamping member 50 to the electrode and then clamp the edges of the grooves 54 so as to substantially encircle and mechanically reinforce the support lead-in members 56.

The resulting structure provides a simple to fabricate clamping member that will provide firm support to the lower .gun element 20 and in addition will give support to the stem lead-ins 56 over their entire length. In addition, it is easy to mechanically secure the clamping member 50 to the stem lead by clamping and in' addition it also lends itself to spot welding to the leads.

While there have been shown and described what are at present considered to be the preferred embodiment of the invention, modifications thereto will readily occur to those skilled in theart. It is not desired, therefore, that the invention be limited to the specific arrangements shown and described and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

We claim as our invention:

1. An electron discharge device comprising an envelope including a tubular portion, an electron gun structure positioned within said tubular portion, said electron gun consisting of a unitary structure of a plurality of electrodes, aligned and spaced, a stem member provided at one end of said tubular portion including a plurality of lead-in support members secured to said stem member and to an electrode of said electron gun adjacent said stem portion, an annular clamping member secured to said adjacent electrode, said clamping member having a plurality of groove portions into which said support lead-ins are positioned and secured therein, said clamping member including extension members also having groove portions therein and into which said support leadins are positioned and secured therein substantially along their length between said stem portion and said adjacent electrode.

2. A cathode ray tube comprising an envelope and including a tubular portion, an electron gun mounted within said said tubular portion, said electron gun comprising a unitary structure comprised of a plurality of tubular shaped electrodes, said tubular shaped electrodes being provided with projecting studs secured to insulating rod members to align and position the electrodes within said unitary structure, astem member provided at the end of said tubular portion for closing off said tubular portion and supporting said electron gun within said tubular portion, a clamping ring secured tothe outer periphery of an electrode of said electron gun adjacent to said stem member, said clamping ring provided with longitudinal projections extending between said electrode and said stern member, said clamping member and said projection members provided with a groove portion, and support leads extending from said stem member to said electrode and positioned and secured within said groove portions for supporting said electron gun with respect to said stem member.

3.-An electron gun assembly having a plurality of electrode elements adapted to be supported in spaced alignment by a plurality of insulative rod members, said electron gun assembly including a control grid electrode comprising a tubular sleeve portion, a stem member provided with a plurality of support lead-in members, a clamping ring mounted on the outer periphery of said sleeve, said clamping ring provided with a plurality of eyelets for receiving said support lead-in members, said leadin members secured within said eyelets, and extension eyelet portions from said clamping member extending between said clamping member and said stern member, said extension portions also receiving and securing said support lead-ins therein.

4. A cathode ray tube comprising an envelope and in cluding a tubular portion, an electron gun assembly mounted within said tubular portion, said electron gun assembly consisting of a unitary structure including a plurality of tubular shaped elements, a plurality of insulating rods provided about said tubular shaped elements and secured to said tubular shaped elements to align and position said tubular shaped elements within said unitary electron gun assembly, a stem member provided at the end of said tubular portion for closing off said tubular portion, a clampingring member secured to the outer periphery of a tubular'shaped element of said electron gun assembly adjacent said stem member, said clamping ring member provided with extension members secured to and extending from said clamping ring toward said stem member, said clamping member and said extension members provided with grooved portions, said stem member including support members extending from said stem member to said adjacent tubular element, said support members positioned and secured from within said grooved portions of said clamping member and extension portions for supporting said electron gun assembly with respect to said stem member.

5. A cathode ray tube comprising an envelope having a .tubular portion, an electron gun assembly positioned within said tubular portion, said electron gun assembly consisting of a unitary structure of a plurality of tubular elements aligned and spaced from each other, a stem member provided at one end of said tubular portion for closing off said tubular portion and comprised of at least three supporting elements mounted in a circumferentiallyspaced array and secured to one of said tubular elements, an annular clamping member secured to the outer periphcry of said one of said tubular elements and having at least three extension portions mounted in a circumferential spaced array corresponding to said support elements, said extension portions of substantially the same length as said support elements and provided with grooved portions for receiving said support elements, said support elements secured within said grooved portions along their length to support said electron gun assembly with respect to.said stem member.

References Cited by the Examiner UNITED STATES PATENTS Re. 25,127 2/62 Szegho 31387 X 2,093,876 9/37 Von Ardenne 313-82.1 X 2,233,795 3/41 Pensak 31382.1 X 2,296,269 9/42 Craig et a1. 31387 X 2,464,076 3/49 Gier 313-82.1 X 3,082,350 3/63 Gulbrandsen 313318 GEORGE N. WESTBY, Primary Examiner.

RALPH G. NILSON, ROBERT SEGAL, Examiner. 

3. AN ELECTRON GUN ASSEMBLY HAVING A PLURALITY OF ELECTRODE ELEMENTS ADAPTED TO BE SUPPORTED IN SPACED ALIGNMENT BY A PLURALITY OF INSULATIVE ROD MEMBERS, SAID ELECTRON GUN ASSEMBLY INCLUDING A CONTROL GRID ELECTRODE COMPRISING A TUBULAR SLEEVE PORTION, A STEM MEMBER PROVIDED WITH A PLURALITY OF SUPPORT LEAD-IN MEMBERS, A CLAMPING RING MOUNTED ON THE OUTER PERIPHERY OF SAID SLEEVE, SAID CLAMPING RING PROVIDED WITH A PLURALITY OF EYELETS FOR RECEIVING SAID SUPPORT LEAD-IN MEMBERS, SAID LEAD-IN MEMBERS SECURED WITHIN SAID EYELETS, AND EXTENSION EYELET PORTIONS FROM SAID CLAMPING MEMBER EXTENDING BETWEEN SAID CLAMPING MEMBER AND SAID STEM MEMBER, SAID EXTENSION PORTIONS ALSO RECEIVING AND SECURING SAID SUPPORT LEAD-INS THEREIN. 